On Sunday, NASA’s Stardust spacecraft began a seven-year journey to visit a
comet. In 2004, the $165-million craft, launched on a Delta-II rocket,
will pass within 160 kilometres of Comet Wild-2.
It will trap dust from the comet and interstellar particles in “aerogel”, a
light, transparent solid. It will then return and drop a capsule containing the
aerogel into the Earth’s atmosphere in 2006. The capsule will land in Utah.
